Switch for telephone-exchanges



2 Sheets-Sheet 1.

G. W. GUY. Switohfor-Telephone-Exchanges. No. 224,@y] Patented Feb. 17,i880.

b e @XM s 2 Sheets-Sheet 2. G. W. C OY.,

Switch for Telephone Exchanges. No. 224,653. Patented Feb.17, |880.

NFETERS, FMOTOMTHOGRAFHER. WASHINGTON. D, c.

UNITED STATES PATENT OFFICE.

GEORGE W. COY, OF NET HAVEN, CONNECTICUT.

SWITCH FOR TELEPHONE-EXCHANGES.

SPECIFICATION forming part of Letters Patent No. 224,653, dated February17, 1880.

Application iiled May 26, 1879.

To all whom it may concern:

Be it known that I, GEORGE W. COY, of New Haven, in the county of NewHaven and State of Connecticut, have invented a new Improvement inElectric Switches; and I do hereby declare the following', when taken inconnection with the accompanying drawings and the letters of referencemarked thereon, to be a full, clear, and exact description of the same,and which said drawings constitute part of this specification, andrepresent, in-

Figure l, front view; Fig. 2, sectional end view; Figs. 3, 4, 5, and 6,detached views; Fig. 7, the telephone as fitted for use; Fig. S, rearview.

This invention relates to an improvement in electric switchesl designedwith special reference to communication by telephone where severalinstruments are arranged upon the same circuit or several circuitscentering at a single point, the object being to receive a call from oneinstrument at the central office for communication with a secondinstrument, and so as to call that instrument, and then put the two incommunication g and the invention consists in the construction, ashereinafter described, and particularly recited in the claims.

A represents the switch-board, on which are keys l, 2, 3, and soon, moreor less, according to the number of circuits or lines. Corresponding toeach line are the switch-spindles a b c, each terminating` in aconvenientlyshaped knob in front. The two spindles b and c are eachprovided with an insulator, d, over a part of their length, for thepurpose hereinafter described. At the inner or rear end of the spindlesthere are arranged three levers, c, f, and B. The one, e, is hungintermediately between the two spindles a b, and so that each of thesaid spindles will be in line with the respective arms of the said levere. The other lever, f, is hung at a point intermediate between the twospindles b c, and so that the said spindles will be in line with thecorresponding end of the said lever f. The lever B is hung centrallybetween the two spindles a c, so that one of its arms will ride upon thelower arm of the lever c and its other arm upon the upper arm of thelever j', as seen in Fig. 4. In this condition the spindle c stands atits extreme inward position and the spindles b a at their outwardposition, and which is the normal condition of the spindles. Now, ifspindle b he pushed in, it will force the spindle c out, or if thespindle a. be pushed in, it will, through the lever B, force the spindlec outward. Either one of the three spindles being in, pushingin eitherot' the other two will force that one out-that is to say, only one ofthe spindles can be in its inward position at the saine time. Abovethese spindles are one or more bars, C D E, each provided with aspindle, h, ["or each circuit, or corresponding to the respective seriesof spindles a b c. Below and on the board, in line with cach series ofspindles a b c, is a metallic plate, F, with a coupling, Z, projectingfrom it toward each spindle IL, as seen in Fig. 5, and the inner ends ofthe spindle lL are constructed so that when forced inward they will makea connection with the coupling, as seen in Fig. 5, but when drawn outare free and away from the coupling. This coupling lis best made ofelastic metal, and the end vof the spindle conical shape, as shown, soas to be forced between the end of the coupling, but may be otherwiseformed.

The line-wire n comes to the board, and comes directly into connectionwith the key of that line shown as l, Fig.^2. Froin the button under thekey a wire, p, runs to the battery, and from the bridge m runs a secondwire, r, to a metallic plate, s, and on this rests an elastic metallicplate or jaw, t, which extends through the board; and on the back awire, a, runs from the jaw t to a point, w, where branches b and c lead,respectively, to make connection with either of the spindles b c. Theseconnections b c are made from strips of metal turned inward against therespective spindles, as seen in Fig. G. In the opposite side of thespindles b c similar strips b2 c2 lead outward. From the one, b2, runsthe ground-wire g, and from the other, c2, the battery-wire B. From thepoint w a wire, f, runs into connection with the metallic plate F, onwhich are the couplings l, to make connection with the spindle h andtheir respective bars.

It will be observed that from the bridge through the plate s and jaw tto the point w the circuit is substantially the saine as if the wire randirect without the interposition of the plate s and jaw t.

The position of the strips b! and b2 relative IOO to the spindles b andc is such that when the spindle is out the ends of those strips restupon the insulator d, but when the spindle b is in then they come incontact with the metal of that spindle and make ground-connection, orwhen the spindle c is in it applies the battery, and the line is readyfor a call.

The use of the elastic jaw t and plate s is to enable the person inattendance to apply a telephone, introducing it to either circuit withwhich 11e wishes to communicate; butinstead ot' the jaw and plate atelephone may be applied to each circuit.

In Fig. 7 the telephone is shown as fitted for introduction between thejaw t and plate s. The two wires of the telephone terminate inwedge-shape metal tips t and t2, with an insulator between. Then theoperator forces this wedge-shape tip between the jaw and plate, andthereby makes connection through the telephone, and is enabled with thissingle telephone to communicate through either of the circuits to whichhe may apply it.

The operation ot' the switch is as follows: The upper spindles, c, areall in, the battery branches thereby being applied to every circuit,each circuit having a bell or other signal at the office, whichindicates a call to the oflice on that circuit. Now, suppose a call tocome from the first circuit, c. The operator pushes in the spindle b onthat circuit, which throws ofi' the battery and puts on the ground. Hethen places his telephone into connection with that circuit, andreceives communication from the person calling', saying, for instance,that he wishes to communicate with a certain person, whom the operatorascertains to be on circuit c3. He then pushes in the spindle a ot' thecircuit c, as in Fig. 3, throwing off yboth battery and ground; thenpushes in the spindle b ofthe circuit c3, and with the key of circuit c3gives the signal required to call that particular person, and introduceshis telephone to the same circuit. The person answering, the operatorgives the information that communication is open for him with the personwho called. He then presses in the spindle a, taking oi' both batteryand ground, and at the same time presses in the spindle h ot' therespective circuits c and c3, making the communication between the twocircuits onl the bar on which are the spindles h. Then, when the partieshave completed their communication, the operator pushes in thebattery-spindle c and draws out the circuit-spindles h, leaving thelines ready for another call.

The object of employing several bars, C D E, is that different circuitsmay be in use at the same time-as, for instance, suppose the iirst andthird are in use, as before described, a call cornes from the secondcircuit to communicate with the fourth, a second bar would be used forconnecting those circuits, and two other circuits would take a thirdbar, and so on. The circuitspindles h are each provided with a spring,as noted in Fig. 2, the tendency of which is to hold the spindlesoutward and prevent accidental connection ofthe circuits.

It will be observed that communication is made from the main wirethrough the key to the switch-board. Hence, when the key is depressed totake it away from the bridge m and make connection with the buttonbelow, the switchboard is cut oftl from the main wire n.

The advantage of this arrangementis as follows: Supposing theswitch-board to be longer than will allow the operator to reach over itsextent, and that a call has come to him from one ofthe extreme circuits.Having received the call, he presses in the lower spindle to disconnectboth battery and ground. Then, having made thc connection with thc barabove, he proceeds to call on the desired circuit, which may be at theother extreme. Having made the call and the connection above with thesame bar, he finds that the called party is not responding. He thenapplies the key to make a recall on that party. Now, if the connectionwere through the switch-board to the keys, as is usual in such switches,the call made on this second circuit would also pass through the bar tothe tirst circuit and make the call upon that circuit also, which wouldat once create confusion, unless the two parties should have thc samesignal; but because of the connection in each circuit being made throughthe key and bridge, it follows that depressing the key from the bridgecuts odi the switch-board, and the signal is made by the contact of thekey with the button, the current passing out through the key directly tothe main wire. Hence the call may be made on any one circuitnotwithstanding that circuit may be in connection with one or more othercircuits, and that call not extend beyond the circuit on which it ismade.

The lower spindle, a, and the levers which connect the several spindlesa b o may be dispensed with, and yet the switch-board be fullyoperative. In that case, however, the operator must work the spindles b@independently of cach otherthat is, pushing in or pulling out, asoccasion may require.

I claim- 1. The switch-spindles a b c, combined with a system of levers,substantially as described, whereby the pressing in of one throws outeither of the others which may happen to be in, substantially as and forthe purpose described.

2. The combination of the spindles a b c, two of which are provided withinsulators with metallic connections, respectively, with the battery andground, whereby either the battery or ground may be applied or both cutofi, substantially as described.

3. The combination of the two spindles b c, arranged to cut o` or apply,respectively, the ground or battery on one circuit, combined with otherseries of like spindles on other inde pendent circuits, and a bar, C,with conplin gs, arranged to place either one of said circuits IOO IIO

IIS

in connection With another of said circuits through said bar.substantially as described.

4. The combination of the two spindles b c, arranged to cut oii orapply, respectively, the ground or battery on one circuit, combined withother series of like spindles on other independent circuits, and two ormore bars, O D E, each provided with couplings arranged to place two ormore of said circuits in connection with two or more otl'lercircnitsthrough said bars, substantially as described.

5. In a switch-board substantially such as described, the combination ofseveral keys, each on an independentcireuit, and each key in directconnection with its particular wire and corresponding bridges connectedto the other Wires, whereby communication from one wire to another withwhich it may be placed in connection must be made through the keys andbridge to the wire of the respective wire, and each of said keys free tosignal through its own wire without communicating such signa'l to theother wire with which it is in connection, substantially as described.

GEORGE W. COY. Witnesses:

Jos. C. EARLE, J. H. SHUMWAY.

